Background: Minimally invasive spinal surgery (MISS) and endoscopic spine surgery (ESS) are both well-established surgical techniques for lumbar spinal stenosis; however, there is limited literature comparing the efficacy of the two techniques with respect to radiological decompression data. Methods: In this review, PubMed, Google Scholar, and Scopus databases were systematically searched from inception until July 2022 for studies that reported the radiological outcomes of endoscopic and minimally invasive approaches for decompressive spinal surgery, namely, the spinal canal area, neural foraminal area, and neural foraminal heights. Results: Out of the 378 papers initially retrieved using MeSH and keyword search, nine studies reporting preoperative and postoperative spinal areas and foraminal areas and height were finally included in our review. A total of 581 patients: 391 (67.30%) underwent MISS and 190 (32.70%) underwent ESS. The weighted mean difference between the canal diameter in pre-operative and post-operative conditions was 56.64 ± 7.11 mm2 and 79.52 ± 21.31 mm2 in the MISS and ESS groups, respectively. ESS was also associated with higher mean difference in the foraminal area postoperatively (72 ± 1 mm2 vs. 35.81 ± 11.3 mm2 in MISS and ESS groups, respectively) but was comparable to MISS in terms of the foraminal height (0.32 ± 0.037 vs. 0.29 ± 0.03 cm in the MISS and endoscopic groups, respectively). Conclusions: Compared to MISS, ESS was associated with improved radiological parameters, including spinal canal area and neural foraminal area in the lumbar spinal segments. Both techniques led to the same endpoint of neural decompression when starting with more severe compression. However, the present data does not allow the correlation of the radiographic results with the related clinical outcomes.

Introduction Microdiscectomy, as of now, is considered the gold standard for the treatment of herniated lumbar disc. It preserves motion at the spinal segment and does not alter the local spinal anatomy significantly, resulting in a “functional and mobile” spine. Development of increasingly better-quality implants has seen their indiscriminate use in cases without any demonstrable instability. We see an increasing number of patients of lumbar disc prolapse being treated by fixation and fusion procedures, without any clear indication or evidence supporting such practice. This adds to the operating time, blood loss, cost of surgery and leads to loss of motion at the spinal segment resulting in a “stiff and immobile spine.” Our 10-year experience of treating lumbar disc herniation by micro-discectomy makes a strong case for preserving the spinal motion segment wherever possible and to use fixation very judiciously only in cases of proven instability. Materials and Methods A total of 295 cases of lumbar disc prolapse operated by the first author from January 2013 to April 2022 were analyzed. All the patients had unilateral or bilateral radicular pain. Preoperatively instability was ruled out by dynamic X-rays. All the patients were operated in prone position on Wilson's frame. Microdiscectomy was done through the inter-laminar space. Patient outcomes and complications were analyzed. Results There was no mortality in our series. All the patients had significant relief of lower limb pain with improved visual analog scale scores postoperatively. The patients were followed up for 6 months. There were complications in 17 patients, all of which were treated successfully with a good outcome. None of the complications were attributable to failure of doing fixation. Conclusion Lumbar disc prolapse can be treated effectively by microdiscectomy. Fixation should be reserved for only those cases with demonstrable preoperative instability.